These experiments are designed to investiate the role of the corpus striatum in behavioral processess other than the motor functions traditionally assigned to the structure. They will investigate the effects of anatomically specific lesions and direct application of crystalline drugs to the corpus striatum of rats on visual, somatosensory, and spatial discrimination performance. The goal is to determine if specific regions of the striatum are preferentially involved in mediting varou behavios, and if these regions use suggested central neurotransmitters in this mediation. Another series of experiments will continue ongoing work on the anatomical and pharmacological specificity of striatal modulation of lateral hypothalamic self-stimulation. Finally, electrophysiological (EEG) measures of arousal will be used to determine the effect of intrastriatally applied 6-hydroxy-dopamine on neocortical and hippocampal electrical activity.